Magnetic storage matrix capable of storing fixed works



Nov. 29, 1966 A. M. SCHULTE ET AL 3,289,178

MAGNETIC STORAGE MATRIX CAPABLE OF STORING FIXED WORDS Filed May a. 1962 1NVENTOR3 ANTHONIUS M. SCHULTE Y JOHANNES STEENBERG M K. AGENT United States Patent 3 289,178 MAGNETIC STURAGE MATRIX CAPABLE OF STORING FIXED WORDS Anthonius Maria Schulte, Delden, and Johannes Steer berg, Ensehede, Netherlands, assignors to North American Philips Company, Inc, New York, N.Y., a corporation of Delaware Filed May 8, 1962, Ser. No. 193,250 Claims priority, application Netherlands, May 10, 1961, 264,643 8 Claims. (Cl. 340-174) The invention relates to a magnetic storage matrix provided with a number of cores consisting of magnetisable material with a large remanence. The matrix is also provided with at least two sets of electrical conductors arranged in such a way that a field can be set up in each of said cores by a current in a certain conductor belonging to a certain one of the sets of conductors and also by a current in a certain conductor belonging to a second set of conductors. In accordance with the invention, at least part of the cores can be made inoperative as storage means by providing a core which is to be made inoperative with a low resistance path for electric currents, which path encloses the core.

Storage matrices of this type are applied in data processing systems, such as electronic computers or electronic control systems, for the purpose of supplying a number of fixed combinations of bits. The supply of a certain combination or word is initiated by causing a current to flow through a certain conductor, belonging, for example, to the first set of conductors. Voltages will then only be induced in such conductors of a second set of conductors which enclose the field set up by the selected conductor from the first set in a core which has not been made inoperative. A core which has been made inoperative does not induce a perceptible voltage. The manufacture of special matrices for special combinations of fixed words is rendered superfluous by this construction. It permits any given combination of fixed words to be produced by a standard storage matrix which has not been especially wound for this combination and which, consequently, is far less expensive than a matrix which has been especially wound. Furthermore, the number of errors in a standard matrix will be less than in a specially wound matrix.

In a known embodiment of such a matrix the complete matrix is embedded in a fiat plastic plate, with the exception of the ring shaped cores, each of which is in a cylindrical opening of the said flat plate. The plate is mounted in a horizontal position and its lower side is covered by a rigid punched card possessing a punching below each opening containing a core which is to be made inoperative for the combination of words stored in the card. Underneath the punched card an elastic container filled with mercury is mounted, and this container is distorted in such a way and to such an extent that the mercury enters those openings containing cores underneath which a punching in the card is present, without, however, reaching the upper side of the plastic plate. The mercury acts as a short circuited winding for every core situated in an opening to which the mercury has obtained access through a punching in the card. Consequently, the cores situated in the openings below which the punching in the card is present are made inoperative. This known method has various disadvantages. It is necessary for the matrix to be mounted horizontally, although, as a rule, the various cards carrying parts of the circuit of a data handling system are mounted vertically. Furthermore the horizontal mounting must be effected very accurately, in order to prevent certain openings from overflowing at the top side of the plate, thus permitting the mercury to enter openings which it should not enter, whilst on the other hand certain openings which should contain mercury will not receive enough of this fluid to form a short circuited path for the cores in the said openings. Also this matrix is unsuitable for transportable data handling apparatus. As a matter of fact, it must be very rigidly mounted so that vibrations of its mounting will not cause the mercury to leave certain openings at the upper side of the plate, as a result of which it might enter openings which should not contain mercury. Furthermore, it may be necessary to provide suitable gaskets and means for pressing the punched card against the plate, or to glue the card to the underside of the plate, in order to prevent leakage of the mercury into openings which should not contain mercury, whilst special measures must be taken in order to prevent drops of mercury from leaving the matrix system and causing short circuits in other circuitry of the data handling system.

The invention avoids all these disadvantages. According to the invention the matrix is built in such a way that the parts of the matrix are carried by a supporting plate, which is provided with an opening opposite to each core which is capable of being made inoperative. A conductor having a certain amount of rigidity passes through each opening facing a core which is capable of being made inoperative from the side opposite to this core and through the opening in this core and back through the opening in the supporting plate to the first mentioned side of this plate. In each opening facing a core which must be inoperative a conductive plug is present which is in electrical contact with each of the two parts of the conductor situated in the opening.

A matrix according to the invention can be mounted in any desired position in the frame of the data handling system. No special measures need be taken in order to prevent leakage of a fluid because the matrix according to the invention does not contain any fluid.

The invention will now be explained by describing two embodiments with reference to the drawings.

FIGURE 1 shows part of a storage matrix of the usual yp FIGURE 2 shows a cross section of a part of a storage matrix according to the invention;

FIGURE 3 shows the front view of the same part.

FIGURE 1 shows part of a storage matrix with ring shaped magnetic cores. This part comprises nine mag netic cores. The ring shaped cores, such as 101 and 102, are shown perpendicular to their axes, so that they are represented by rectangles. The core material shows a substantial remanence so that its hysteresis loop is more or less rectangular. Each ring-shaped core is arranged so as to form part of a column running from the top of the drawing downwards and of a line running from left to right on the drawing. In the embodiment shown in FIGURE 1 these columns and lines are straight and mutually perpendicular. The magnetization of a core has a certain direction if a core stores a bit of a certain type, e.g. a 1 bit, and the opposite direction if it stores a bit of the other type, such as a 0 bit. Three sets of conductors are provided in this embodiment for the purpose of exciting the cores. Each conductor of the first set, such as the conductors 103 and 104, runs from the top downwards passing through the rings of a column of cores.

Each of the conductors of the second set, such as the conductor 105, runs from left to right, passing through the cores on the same line. There is also a third conductor passing through all the rings of the complete storage matrix. This conductor is shown in the figure as a set of conductors such as 106, each of which passes through the rings of a line, all these conductors being connected in series. It is, however, not necessary for the conductors of the third set to have the same direction as the conductors of one of the other sets. It sufiices if conductors connected in series are present which pass in the same direction through all cores of the matrix. These conductors may have a direction which is oblique with respect to the directions of the conductors of the other sets. The operation of such a matrix is well known in the art and needs little explanation. A current with the strength i passes through the conductors of the third set, such as 106. This current supplies i ampere-turns for each core, and is not strong enough to exert a perceptible influence on the magnetization of the cores with a large remanence through which these conductors pass. The field strength remains within the part of the magnetization curve in which only a very small change in the magnetization occurs.

The various bits of a word or sign are stored by the various cores of a single line. During an operation, generally called writing, the magnetization of each core on the line by which a word must be stored is given the direction corresponding to the character of the bit to be stored by it. During this writing operation only a field with a certain direction can be set up in the cores, so that the writing currents are only able to magnetize the cores in a direction corresponding to a certain type of bit. Magnetization corresponding to the other type of bit must result from the absence of a sufiiciently strong writing field during the writing operation. Consequently, previous to the writing operation all the cores of the line must be magnetized in the direction opposite to that of the writing field. This is efiected during the reading operation, as Will be shown below. During this operation the cores of a line are magnetized in a direction corresponding to the direction of the field set up by the current with the strength i in the conductors of the third set. If a word is to be written on the upper line of the matrix shown in FIGURE 1, a current with the strength of 2i and a direction opposite to the direction of the constant current in the conductor 106 is caused to flow through the conductor 105. Because the fields set up by the currents in the conductors 105 and 106 have opposite directions, no more than i ampere-turns are available for the cores on the said line. If during the writing operation the magnetization of the cores 107 must obtain a direction which is opposite to that resulting from the reading operaion, a current with a strength which is also 21 and with such a direction that its field supports the field set up by the current in the conductor 105 is caused to flow through the conductor 103. Then 3i ampereturns are available for magnetizing the ring core 107, which is sufiicient for reversing the magnetization of this core. Magnetization in this direction indicates that the said core stores a 1 bit.

If the word stored by the said line is to be read, then a reading current with a strength 2i and such a direction that its field has the same direction as the field set up by the current in the conductor 106 is caused to fiow through the conductor 105. In this case too 31' ampereturns are available for the cores of the upper line. The direction, however, is opposite to the direction of the field which effected the writing operation. If the direction of the magnetization of a core has not been reversed during the writing operation, the reading current in the conductor 105 has no eifect. If the direction of the magnetization of a core has been reversed during the writing operation this direction is again reversed. In the absence of special measures this reversal of the magnetization induces a voltage pulse in a conductor, such as 103, which passes through the said ring core from the top downwards, and this voltage pulse indicates that a 1 bit has been read.

According to the invention, if the occurrence of such a pulse is to be prevented, an electric circuit with a low resistance is provided which encloses the field in said core. This circuit does not prevent the direction of magnetization from being reversed by the reading current, but this reversal causes a relatively strong current to flow in the low resistance circuit, which, as a result of the self-inductance of this circuit, is maintained during a relatively long interval. According to the induction law this current opposes the field change causing it. Consequently the reversal of the magnetic field in the ring 107 enclosed by the conductor 103 will progress at a substantially slower rate than in the absence of the said circuit with low resistance enclosing the core. The voltage induced in the conductor 103 is proportional to the rate of change of the field in the core, so that it will be much lower when a short circuited winding is present on the core than when no such winding is present. The presence of a short circuited winding on a core causes such a reduction in the amplitude of the pulse induced in the conductor 103 that, by very simple means, such as a simple threshold circuit, the system cooperating with the matrix can be made insensitive to the pulses supplied by a core with a short circuited winding. Such short circuited windings on certain cores adapt a matrix storage to the task of supplying a number of fixed words. Each of these words is stored on a line of the matrix by providing the cores which are not to supply voltage pulses for the said word with such a short circuited winding. If one of the fixed words is to be read-out of a particular line of the matrix, then all of the cores of that line must first be magnetized in the direction corresponding to a 1 bit. This is accomplished by causing a current of 2i to flow in each of the column conductors 103, 104, while simultaneously establishing a current of 2i in the horizontal conductor 105 for the particular line to be read-out. If desired, all the cores of the matrix may, for this purpose, be magnetized in the said direction by currents in all the horizontal and in all the vertical conductors of this matrix. Then if the word stored in a certain line by means of short circuited windings on certain cores of this line is to be supplied, this is initiated by causing a reading current to flow in the horizontal conductor, such as 105, of the said line. This current, together with the current in the conductor 106, causes the magnetization of all the cores of the said line to be reversed. This reversal will induce sufficiently strong pulses only in those vertical conductors enclosed by ring cores on the said line which do not carry short circuited windings.

It is important that the matrix be built as a standard matrix which can be set in accordance with any group of desired words, and that the settings can be changed by an easy procedure. The matrix according to the invention satisfies these requirements. Two embodiments of such a matrix will be described with reference to FIG- URES 2 and 3. In these figures only two ring cores of the matrix are shown, whilst, moreover, only the conductors in a certain direction are represented. The complete matrix is carried by a plate of insulating material 205. Each ring core in this matrix is situated in front of an opening in this plate, such as 206, 210 or 310. These openings have such a diameter that a core, such as 201, 204 or 304, can easily pass through it. The matrix possesses a crenel-shaped wire either for each line or for each column. This wire passes through each opening of the column from the right hand side of the supporting plate 205 to the left hand side, then encloses the core situated in front of the opening and passes back through the opening to the right hand side of the plate. Preferably such a wire 202, 302 is also applied as part of a conductor of one of the sets of conductors which pass through the rings in a certain direction. The figure shows a second wire 203 passing in the same direction through the rings of the same column. This may be a conductor from another set, but may also be the continuation of the same conductor passing for the second time through all the rings, e.g. in order to increase the amplitude of the voltage pulses induced in the said wire or to make a smaller magnetizing current sufiice for a given magnetization. The conductors of the set(s) of con ductors which are perpendicular to the plane of the drawing are not shown. A ring core, such as the ring 204, can be made non-operative by introducing a plug of conductive material into the opening of the plate 205 in front of which the ring is situated. The figure shows two different constructions for such plugs. The lower plug 211, 311 is shaped more or less like the split contactpin of a power plug. This plug must be introduced into the opening in such a position that its slit engages with the two parts of the wire 202, 302, located in the opening, whereby the wires become clamped in the slit. In this way a short circuited winding is established which encloses the magnetic field in the core 204 and consists of a part of the wire 202 and the plug introduced into the opening. In order to prevent a plug which is being removed from an opening from carrying the wire 202, 302 with it, and in this way causing damage to the ring, or the wires passing through this ring a thin plate 209, 309 of insulating material, which is connected to the supporting plate 205, encloses the wires 202, 302 and fixes them to the supporting plate. Openings in this plate 209, 309 are provided in order to make the openings in the plate 205 accessible to the plugs. The plug 211 is of a type which requires a circular opening. Such a plug has the disadvantage that the correct position in which the slit coincides with the wires must be found by trial. In this respect the plug 208, 308 is to be preferred. This type of plug is made by bending a certain length of elastic conductive strip material into the described shape. The dimensions of this plug are such that the breadth of the strip differs from, and in the embodiment shown, is larger than the distance between the two parts of the strip which are situated in the opening 207, 307 of a covering plate of insulating material 209 when the plug has been introduced into the matrix. The opening in the covering plate of insulating material 209, 309 is adapted to the dimensions of the plug. Consequently this plug can only be inserted into the opening in the correct position. When the plug is in the opening the elastic extremities of the plug rest against the two parts of the wire 202, in this way effecting the required short circuit.

In a practical embodiment the ring shaped cores are not perpendicular to the direction of the conductors such as 202, but form an angle of 45 degrees with this direction so that the wires of the two sets of conductors may be carried more easily through the ring cores.

The matrix can be built in a very simple way. To begin with the crenal shaped wires are bent into their shape, e.g. by special bending apparatus. Such a prefabricated wire of the correct length is introduced into a bin containing ring cores, as a result of which a number of ring cores automatically slip onto the wire. Experience has shown that it is very easy to shift a ring into each crenel without leaving rings in between by simply shaking such a wire with rings on it. This having been effected the crenel shaped parts of such a wire carrying the rings are introduced into a column or line of openings of a supporting plate such as 205, which, for this purpose, is placed horizontally. Then the covering plate 209 is mounted and fixed to the supporting plate, after which the other conductors are passed through the cores.

It is obvious that it is not necessary for the crenel shaped wires to have the same direction as the columns. They can also be aranged along the lines. If the crenel shaped wires are not used as part of one of the sets of wires mentioned above, or if they are used to carry the current with strength which is used to bias the cores and flows continuously, it is then not necessary for these crenel shaped wires to have the same direction as the conductors of the sets. They may be arranged so as to have an arbitrary direction, e.g. a direction which forms an angle of 45 with the direction of the conductors of the two sets, so that the rings will automatically obtain a direction which encloses an angle of 45 with the two sets of wires. This is desirable in order that these wires may be more easily carried through the ring cores. In this case, and also when the crenel shaped wires are in the direction of the columns or the lines, but do not form part of one of the sets of conductors, care must be taken that these wires do not form part of a closed circuit for the pulses, for in this case a reversal of the magnetization of a certain ring would be able to induce a current in such a closed circuit and thereby influence the magnetization of other rings.

It would be possible to build a storage matrix according to the invention in which separate crenel shaped wire elements are used, each of which is present in an opening in the supporting plate, without these separate parts being connected so as to form a conductor. It is obvious that such a construction is part of the invention, but it is equally obvious that such a construction would be more expensive to manufacture, even should the crenel shaped wires of the embodiment described above not be used as a conductor in one of the sets of conductors.

It is obvious that it is by no means necessary for a matrix to possess three sets of conductors in order to be able to effect the operations described above. Moreover, it is not necessary for the magnetization of the cores to be effected by currents in conductors belonging to more than one set of conductors. The construction described has been selected because standard storage matrixes as a rule possess three sets of wires, and because if three sets of wires are used, the circuit cooperating with the matrix then may be of a standard type, as used in combination with matrix storages used for storing variable signals or words. If, moreover, in a matrix having three sets of wires, and used for fixed words, certain lines are not used for this purpose, these lines may be applied for storing variable words, which in this case can be read and written by the same standard reading and writing circuit used for reading the fixed words. If a matrix is used only for supplying fixed words, and if it is desirable for this matrix to be as simple as possible, then two sets of conductors are sufficient. In this case one of these sets may be the set which, in the drawing, runs from the top downwards, and is used for supplying the pulses generated in these wires by the changes in the magnetization of cores enclosed by these wires. The second set of wires may be one of the sets, which, in the drawing, runs from left to right. If such a storage matrix is to supply a certain signal, a current is first causes to flow through the horizontal wire belonging to the line on which the said signal has been permanently set. The strength and the direction of this current are such that the cores on this line are magnetized to such an extent and in such a direction that a reversal of the magnetization induces a pulse with the required strength and polarity in a vertical conductor enclosing such a core. The eventual supply of the signal is initiated by a current in the said horizontal wire with the same strength but the opposite direc tion. This current causes the magnetization of all the cores on the line to be reversed. As has been described above pulses will be induced only in those vertical wires which enclose the field of a core on the said line which does not carry a short circuited winding. In such a matrix it is superfluous for the vertical wires, such as 103 and 104, to carry any current for the purpose of preparing the storage matrix for supplying one of its fixed words.

What we claim is:

1. A magnetic storage matrix comprising a plurality of magnetic cores each of which is constituted of a material possessing a large remanence, a plurality of first electrical conductor means linking each of said cores, a plurality of second electrical conductor means linking each of said cores, a plate for supporting said cores having a plurality of openings therein, each of said openings being located adjacent a particular core, said second conductor means comprising a crenel shaped conductor having a plurality of crenels wherein each crenel comprises first and second portions mounted in an individual opening in said plate and a third portion linking the adjacent core, and means for effectively disabling particular cores of said matrix, said disabling means comprising a conductive plug mounted in an opening of said plate in contact with said first and second portions of said crenel shaped conductor.

2. A magnetic storage matrix comprising a plurality of magnetic cores arranged in rows and columns, each of said cores being composed of a material having a substantially rectangular hysteresis loop and a large remanence, a first and second set of electrical conductors threading said cores, each of said cores enclosing one conductor out of each set of conductors, a support plate for said cores having an opening therethrough opposite each of said cores, a crenel shaped conductor having a plurality of crenels arranged so that each crenel passes through said opening in said plate and through the core opposite said opening and then back through said opening in the plate, and means for effectively disabling particular cores of said matrix comprising a conductive plug mounted in the associated opening in said plate and in contact with the two parts of the crenel shaped conductor passing through the opening in which said plug is mounted.

3. Apparatus as described in claim 2 wherein said crenel shaped conductor links all of the cores in a line of cores in said matrix and wherein said crenel shaped conductor comprises one conductor of said pair of conductors.

4. A magnetic storage matrix comprising an array of apertured magnetic cores composed of a material having a substantially rectangular hysteresis loop and a large remanence, a plurality of first conductor means threaded through each of said cores, a plate for supporting said cores having a plurality of openings therein, each of said openings being located adjacent a different preselected core, a plurality of second conductor means each comprising a crenel shaped conductor having a plurality of crenels, each of said crenels comprising first and second leg elements located in an opening in said plate, an extension of said leg elements threading the adjacent core on one side of said plate and a base portion extending out of the opposite end of said opening and parallel to the plane of the plate, a cover plate mounted adjacent said support plate on the side thereof opposite said array of cores, said cover plate including a plurality of openings in registration with individual openings in said support plate, and means for effectively disabling particular cores of said array comprising a plurality of conductive plug members mounted in openings of said support plate in contact with said first and second leg elements of said crenel located therein.

5. Apparatus as described in claim 4 wherein said sup- 1 port plate and said cover plate are composed of electric insulating material and said crenel shaped conductor is composed of a material which is sufliciently rigid so as to maintain its crenel shape.

6. Apparatus as described in claim 4 wherein said plug comprises an elastic strip of conductive material bent to form two elastic ends capable of being inserted into an opening of said support plate, said cover plate opening having a cross-section having two unequal dimensions, said elastic strip being compressible so that the minimum distance between the ends of said strip is at most equal to one of said dimensions of said cover plate opening, said strip having a width dimension different than said one dimension of said cover plate opening whereby said plug can only be inserted into said cover plate opening in such a position that each of the elastic ends thereof are in contact with one of said leg elements of said crenel shaped conductor located in said support plate opening.

7. Apparatus as described in claim 4 wherein said plug comprises an elastic strip of conductive material having a non-regular rectangular cross-section having a length and width dimension and bent to form two elastic ends capable of being inserted into an opening of said support plate, said cover plate opening having a non-regular rectangular cross-section having a length dimension and a Width dimension, the width dimension of said elastic strip being at most equal to said length dimension of said cover plate opening whereby said plug can only be inserted into said cover plate opening in such a position that each of the elastic ends thereof are in contact with one of said leg elements of said crenel shaped conductor located in said support plate opening.

8. A magnetic storage array comprising a plurality of apertured magnetic cores composed of a magnetic material having a large remanence, a plate for supporting said cores having a plurality of apertures therein, each of said apertures being located adjacent a particular core, a first and a second set of electrical conductors threading said cores, each of said cores enclosing a conductor of said first set and a conductor of said second set of conductors, at least one crenel shaped conductor having a plurality of crenels wherein each crenel comprises first and second portions positioned in an individual aperture in said support plate and a third portion passing through the aperture of the adjacent core, and means for effectively disabling particular cores of said array, said disabling means comprising, for each core to be disabled, a onductive plug mounted in an aperture of said supporting plate in contact with said first and second portions of the crenel positioned in said aperture.

References Cited by the Examiner UNITED STATES PATENTS 6/1962 Grenchus 340174 4/1964 Merz 340-174 

1. A MAGNETIC STORAGE MATRIX COMPRISING A PLURALITY OF MAGNETIC CORES EACH OF WHICH IS CONSTITUTED OF A MATERIAL POSSESSING A LARGE REMANENCE, A PLURALITY OF FIRST ELECTRIC CONDUCTOR MEANS LINKING EACH OF SAID CORES, A PLURALITY OF SECOND ELECTRICAL CONDUCTOR MEANS LINKING EACH OF SAID CORES, A PLATE FOR SUPPORTING SAID CORES HAVING A PLURALITY OF OPENINGS THEREIN, EACH OF SAID OPENINGS BEING LOCATED ADJACENT A PARTICULAR CORE, SAID SECOND CONDUCTOR MEANS COMPRISING A CRENEL SHAPED CONDUCTOR HAVING A PURALITY OF CRENELS WHEREIN EACH CRENEL COMPRISES FIRST AND SECOND PORTIONS MOUNTED IN AN INDIVIDUAL OPENING IN SAID PLATE AND A THIRD PORTION LINKING THE ADJACENT CORE, AND MEANS FOR EFFECTING DISABLING PARTICULAR CORES OF SAID MATRIX, SAID DISABLING MEANS COMPRISING A CONDUCTIVE PLUG MOUNTED IN ONE OPENING OF SAID PLATE IN CONTACT WITH SAID FIRST AND SECOND PORTIONS OF SAID CRENAL SHAPED CONDUCTOR. 